<template>
        <!-- 商品分类导航 -->
        <div class="type-nav">
            <div class="container">
                <!-- 将[全部商品分类]和三级菜单包在同一个div中,利用事件委托,解决鼠标移入移出样式的切换及鼠标在移出[全部商品分类]后,索引为零的样式消失 -->
                <div @mouseleave="leaveShow" @mouseenter="enterShow">
                <h2 class="all">全部商品分类</h2>
                <transition name='sort'>
                <div class="sort" v-show='isShow'>
                    <div class="all-sort-list2" @click="goSearch">
                        <div class="item bo" v-for='(c1,index) in categoryList' :key='index' >
                            <h3 :class='{cur:currentIndex==index}'  @mouseenter="changeIndex(index)">
                                <a :data-categoryName='c1.categoryName' :data-category1Id='c1.categoryId' href="javascript:;">{{c1.categoryName}}</a>
                            </h3>
                            <div class="item-list clearfix" :style="{display:currentIndex==index ? 'block' : 'none'}">
                                <div class="subitem">
                                    <!-- 二级菜单 -->
                                    <dl class="fore" v-for='(c2,index) in c1.categoryChild' :key='c2.categoryId'>
                                        <dt>
                                            <a :data-categoryName='c2.categoryName' :data-category1Id='c2.categoryId' href="javascript:;">{{c2.categoryName}}</a>
                                        </dt>
                                        <dd>
                                            <em v-for='(c3,index) in c2.categoryChild' :key='c3.categoryId'>
                                                <a :data-categoryName='c3.categoryName' :data-category1Id='c3.categoryId' href="javascript:;">{{c3.categoryName}}</a>
                                            </em>
                                           
                                        </dd>
                                    </dl>
                                </div>
                            </div>
                        </div>
                    </div>
                </div>
                </transition>
                </div>
                <nav class="nav">
                    <a href="###">服装城</a>
                    <a href="###">美妆馆</a>
                    <a href="###">尚品汇超市</a>
                    <a href="###">全球购</a>
                    <a href="###">闪购</a>
                    <a href="###">团购</a>
                    <a href="###">有趣</a>
                    <a href="###">秒杀</a>
                </nav>
            </div>
        </div>  
</template>

<script>
import {mapState} from 'vuex'
// 引入lodash
import throttle from 'lodash/throttle'
export default {
    name:'TypeNav',
    data(){
        return {
            currentIndex:-1,
            isShow:true
        }
    },
    computed:{
        ...mapState({
            categoryList:(state)=>state.home.categoryList
        })
    },
    methods:{
        // 节流处理
        changeIndex:throttle(function(index){
            this.currentIndex=index
        },20),
        // 跳转search页面 事件委托
        goSearch(e){
            let node=e.target
            let {
                categoryname,
                category1id,
                category2id,
                category3id,

            }=node.dataset
            if(categoryname){
                let location={name:'search'}
                let query={categoryName:categoryname}
                if(category1id){
                    query.category1Id=category1id
                }else if(category2id){
                    query.category2Id=category2id
                }else{
                    query.category3Id=category3id
                }
                location.query=query
                if(this.$route.params){
                    location.params=this.$route.params
                    this.$router.push(location)

                }
            }
        },
        // 控制三级菜单的在对应组件的显示与隐藏
        leaveShow(){
            this.currentIndex=-1
            if(this.$route.path !='/home'){
                this.isShow=false
            }
        },
        enterShow(){
            if(this.$route.path !='/home'){
                console.log(1)
                this.isShow=true
            }
        }
    },
    mounted(){
         if(this.$route.path !='/home'){
                this.isShow=false
            }
    }
   
}
</script>

<style scoped lang='less'>

    .type-nav {
        border-bottom: 2px solid #e1251b;

        .container {
            width: 1200px;
            margin: 0 auto;
            display: flex;
            position: relative;

            .all {
                width: 210px;
                height: 45px;
                background-color: #e1251b;
                line-height: 45px;
                text-align: center;
                color: #fff;
                font-size: 14px;
                font-weight: bold;
            }

            .nav {
                a {
                    height: 45px;
                    margin: 0 22px;
                    line-height: 45px;
                    font-size: 16px;
                    color: #333;
                }
            }

            .sort {
                position: absolute;
                left: 0;
                top: 45px;
                width: 210px;
                height: 461px;
                position: absolute;
                background: #fafafa;
                z-index: 999;
                

                .all-sort-list2 {
                    .item {
                        h3 {
                            line-height: 30px;
                            font-size: 14px;
                            font-weight: 400;
                            // overflow: hidden;
                            padding: 0 20px;
                            margin: 0;

                            a {
                                color: #333;
                            }
                            &.cur{
                                background-color: yellowgreen;
                            }
                        }

                        .item-list {
                            display: none;
                            position: absolute;
                            width: 734px;
                            min-height: 460px;
                            background: #f7f7f7;
                            left: 210px;
                            border: 1px solid #ddd;
                            top: 0;
                            z-index: 9999 !important;

                            .subitem {
                                float: left;
                                width: 650px;
                                padding: 0 4px 0 8px;

                                dl {
                                    border-top: 1px solid #eee;
                                    padding: 6px 0;
                                    overflow: hidden;
                                    zoom: 1;

                                    &.fore {
                                        border-top: 0;
                                    }

                                    dt {
                                        float: left;
                                        width: 54px;
                                        line-height: 22px;
                                        text-align: right;
                                        padding: 3px 6px 0 0;
                                        font-weight: 700;
                                    }

                                    dd {
                                        float: left;
                                        width: 415px;
                                        padding: 3px 0 0;
                                        overflow: hidden;

                                        em {
                                            float: left;
                                            height: 14px;
                                            line-height: 14px;
                                            padding: 0 8px;
                                            margin-top: 5px;
                                            border-left: 1px solid #ccc;
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }
            .sort-enter{
                height: 0px;
                opacity: 0;

            }
            .sort-enter-to{
                height: 461px;
                opacity: 1;
                overflow: hidden;
            }
            .sort-enter-active{
                transition:all .5s linear;
            }
        }
    }
</style>